Haemolytic jaundice is caused due to a dominant gene but only $10\%$ of the people actually develop the disease. A heterozygous man marries a homozygous normal woman; what proportion of the children would be expected to develop the haemolytic disease

• A

  $1/5$

• B

  $1/10$

• C

  $1/15$

• D

  $1/20$